Connector for aircraft windshields

ABSTRACT

A connector is provided for the leads from a resistance-type windshield heater embedded in the windshield in order to facilitate connection of these leads to a power supply. The connector is formed of a pair of insulating blocks with openings therein making a loose fit with metallic connector inserts, each having a transverse opening designed to receive the bare end of a heater lead and registering with a transverse groove in one of the blocks in order that soldered connections may readily be made. Accordingly, a block containing the leads from the power supply may be attached to the connector block of the present application with the terminals in the power supply terminal block in positive contact with the metallic inserts in order to avoid any possibility of arcing or poor electrical connection between the inserts and the terminals in the power supply connector block.

[451 Jan.18,1972

[54] CONNECTOR FOR AIRCRAFT WINDSHIELIDS Joseph M. Wallace, 5898 Blackwelder Street, Culver City, Calif. 90230 [22] Filed: Sept. 10, 1969 [21] Appl. No.: 856,726

[72] Inventor:

[52] U.S. Cl. ..339/198 R, 339/207 R, 339/272 A [51] Int; Cl ..H0lr 9/10 [58] Field of Search ..2l9/522, 213; 339/l98,206,

3,380,017 Gomulka ..339/207 S Bel 4/ l5 OTHER PUBLICATIONS IBM Tech. Disc. Self-Locking Socket," T. Kehagioglov, l969- 03 Vol. II, No. 10

Primary Examiner-Marvin A. Champion Assistant Examiner-Robert A. Hafer AttorneyFrederic B. Schramm [57] ABSTRACT A connector is provided for the leads from a resistance-type windshield heater embedded in the windshield in order to facilitate connection of these leads to a power supply. The connector is formed of a pair of insulating blocks with openings therein making a loose fit with metallic connector inserts, each having a transverse opening designed to receive the bare end of a heater lead and registering with a transverse groove in one of the blocks in order that soldered connections may readily be made. Accordingly, a block containing the leads from the power supply may be attached to the connector block of the present application with the terminals in the power supply terminal block in positive contact with the metallic inserts in order to avoid any possibility of arcing or poor electrical connection between the inserts and the terminals in the power supply connector block.

18 Claims, 5 Drawing Figures PATENTED Juli 8 I972 5 m F a;

4 m. F 3 M F INVENTOR. JOSEPH M. WALLACE ATTOQNEY.

CONNECTOR FOR AIRCRAFT WINDSHIELDS PRELIMINARY DESCRIPTION Resistance wires have been embedded in Windshields to serve as windshield heaters, particularly for aircraft Windshields. Leads are brought out toward the edge of the windshield for making electrical connections to leads from the electrical power supply. The leads from the electrical power supply are ordinarily provided with a connector block. Especially on aircraft, a compact form of power supply connector block such as described in my U.S. Pat. No. 2,984,816 is desirable. Such power supply connector blocks have terminals therein. For making electrical connections between these terminals and the leads from the windshield heater wires, nut plates have been embedded in the windshield with the leads soldered to the nut plates.

It is an object of the present invention to facilitate the soldering of leads to nuts or elements employed for making connections with the terminals of the power supply connector block and also to assure that the confronting surfaces of the parts being electrically connected will be in positive contact and can be drawn together very tightly without any danger of poor electrical connections, arcing or the like and, in addition, avoiding a possibility that any strain will be put upon the windshield or attachments thereto in an effort to draw electrically connecting parts together tightly, especially in the case of nut plates or the like embedded in the windshield which may have become slightly canted or set too low or too high to permit proper electrical contact with all of the terminals of the power supply connector block.

In carrying out the present invention in its preferred form a two-part connector unit is employed comprising two insulating blocks having openings or cavities therein for receiving metallic inserts so designed that the ends of the leads from the windshield heater may readily be soldered to the inserts and the inserts are mounted so as to make a loose fit in the insulator blocks such that the ends of the inserts may be drawn into position positive contact with the terminals of the power supply connector block. The two insulator blocks of the connector of the present invention are secured to each other after the inserts have been mounted therein so that the connector block formed is a unitary assembly which may be mounted in or on the edge of the windshield or in a portion of the frame forming a mounting for the windshield.

A better understanding of the invention will be afforded by the following detailed description considered in conjunction with the accompanying drawings in which:

DRAWINGS FIG. 1 is a plan view, fragrnentan'ly showing the edge portion of a windshield with a power supply connector terminal block of the type illustrated in my U.S. Pat. No. 2,984,816 in place upon a windshield connector block forming the subject matter of my present invention,

FIG. 2 is a plan view of the connector assembly of FIG. 1 with a portion of the connectors broken away, showing the manner in which the inserts of the power supply terminal block are brought into electrical contact with metal inserts receiving the ends of windshield heater leads in a windshield connector,

FIG. 3 is a view of a cross section of the windshield connector of FIG. 2 showing the manner in which the connection to the windshield heater lead is made and showing the power supply connector in place,

FIG. 4 is a perspective view of one of the metal inserts of the windshield connector of FIGS. 2 and 3 and FIG. 5 is an elevation of a modified form of windshield connector insert for use with very large Windshields where braided, rectangular cross section leads are required for windshield heaters carrying heavy current.

Like reference characters are utilized throughout the drawing to designate like parts.

DETAILED DESCRIPTION In the embodiment of the invention illustrated in FIGS. 2, 3, and 4, the windshield connector comprises a pair of insulating blocks Ill and 12 containing connector inserts l3 and held together by a suitable means such as screws M and nuts 15. The connector inserts 13 are designed to receive the ends of current supply leads 16 to schematically represented resistance wires 10 embedded in a conventional manner in a windshield represented fragmentarily at 18 in FIG. 1. Insulating dielectric sleeving 17 is provided for the leads in which permit travel of the lead 16 within the sleeve 17.

The windshield connector ll, l2, 13 is designed for making reliable electrical connections to a power supply connector of the type having terminals with electrical contact surfaces lying in a plane constituting the plane of a power supply connector block. An example of such connectors is illustrated in U.S. Pat. No. 2,984,816. Such power supply connectors comprise a molded insulating block 21 having a lower plane surface 22 and having power supply terminals 23 molded into the block 21. Each of the terminals 23, composed of a suitable metal such as copper has a lower electrical contact surface 24, preferably silvered, lying in substantially the same plane as the plane 22 forming the lower surface of the insulator block 211. Power supply leads 25 are connected to an aircraft bus bar, suitable junctions, a terminal block or some other source of power within the aircraft. As explained more fully in the aforesaid U.S. Pat. No. 2,984,8l6, the leads 25 are joined to inserts 23.

It is important that the nut or other member forming the electrical connection from the windshield heater wire leads I7 make positive electrical contact with the silvered surface 24 of the power supply terminal 23 in order to avoid arcing, and buildup of resistance, which could lead to heat, corrosion or other problems and eventual failure including the destruction of the heater wire leads. This is a serious problem since Windshields, particularly for large aircraft, are very costly.

The windshield connector of the present application is so designed that the connector insert 13 is located in alignment with the power supply connector terminal 23 with confronting surfaces exactly parallel and with the insert 13 capable of being drawn up in positive contact against the power supply connector terminal 23. To this end the connector insert 13 is formed to be substantially cylindrical and openings therefor are formed in the insulator block ii and 12 of such size as to form a slip fit or loose fit so that there is no hindrance to the insert 13 being drawn up against the power supply connector terminal 23 and with positive contact across the entire upper end surface 26 of the insert 113 with the lower surface 24 of the terminal 23.

The insert 113 is formed with a neck 27. A noncircular, flatsided or polygonal collar such as a hexagonal collar 28 is formed around a portion of the insert 13 which is to lie within the upper insulator block ll of the windshield connector in order that the insert 13 will be retained within the block without turning when the blocks Ill and T2 are fastened to each other. In addition the block ii is formed with an opening 29 having a dimension slightly greater than the hexagonal portion 28 of the insert E3 to provide a loose fit, but with an over hang 31 around the upper edge of the opening 29 adapted to prevent the collar 28 from slipping upward through the opening 29. It will be understood that the overhang 31 is of greater diameter than the portion 32 of the insert 13 and of somewhat less vertical dimension in order to provide adequate clearance space 33 for permitting the surface 26 of the inserts 13 to be drawn up against the surface 241 of the terminal 23 in positive contact therewith. Nevertheless, upward travel of the insert 13 is sufficiently restricted to prevent it from riding up so high as to interfere with compression and sealing action of the ring or gasket 49 around the bottom of the terminal 23.

For receiving the portions 27 and 35 of the insert 13 the lower insulator block 12 of the windshield connector is formed with a socket 36. it will be understood that the transverse and longitudinal dimensions of the socket 36 are also sufficient to enable the insert 13 to move freely and to adjust its position as may be needed to enable the upper end surfaces 26 of all of the inserts 13 in the block to lie exactly in the plane of the surfaces 22, 34, and 24.

Elongated grooves 36 of adequate dimensions to receive the heater lead wires 16 and sleeving 17 are provided in the lower block 12 extending transversely therefrom as shown in FIG. 2. Moreover, the grooves 37 are extended beyond the expected displacement vertically of the lead wire 16 and sleeving 17 to assure full freedom of movement of the inserts 13. The inserts 13 are provided with transverse recesses or openings 38 so located that the openings 38 will be substantially in alignment with the conductor 16 in the sleeving 17 when the apparatus is assembled.

Preferably the ends of the transverse openings 38 are chamfered or countersunk as shown at 39 to facilitate causing solder to run into the joint between the end of the lead 16, preferably silvered, and the metal around the opening 38 in the insert 13 when a hot iron is touched to the lower end of the portion 27 of the insert 13 with the up of a string of solder applied to the chamfer 39. This construction of two insulator blocks 11 and 12 and removable terminal members 13 makes readily accessible both terminal and lead, so that a satisfactory starting point is easily obtainable even though the lead is cut to minimum length and results in very little excess after assembly. It also permits the use of a dielectric tubing over the lead.

After the joints have been soldered the windshield blocks are assembled by bringing the blocks 11 and 12 together with the portions 35 of the inserts 13 in the sockets 36, and the opening 29 of the block 11 surrounding the remaining portion of the insert 13. The blocks 11 and 12 are then fastened together by means of the screws 14. The nuts for engagement with the screws 14 are molded in hexagonal spaces 41 in the lower block 12 to make sure of proper alignment with the upper block 11.

The windshield connector block is then secured in any desired manner to the windshield 18. For example, if a recess has been formed in the edge of the windshield 18, the blocks 11 and 12 may be secured in the recess by a simple means such as cement 42. The invention does not however, exclude mounting the windshield connector blocks in some other manner as by cementing or bolting to a framework constituting a common support for the windshield 18 and the windshield connector block l1, 12.

After the windshield connector block has been secured, electrical connections are made to the power supply leads 25 by bringing the power supply connector block 21 into position and inserting electrical connection screws 43. Owing to the loose fit forthe insert 13 which has been provided in insulator blocks 11 and 12, the tightening of the screw 43 serves to bring the electrical contact surfaces 26 and 24 of the insert 13 and the power supply terminal 23 into positive electrical contact and to form a good, high-conductivity, electrical joint.

Although the invention has been described as carried out utilizing an insert 13 with a circular transverse opening 38 for receiving circular wire or stranded windshield heater lead wires bundled into circular form, the invention is not limited thereto and does not exclude arrangements adapted for receiving rectangular cross section lead wires. For example, as illustrated in FIG. 8, when the windshield is of such size as to require higher power heaters and larger cross section heater wire leads, a flat or rectangular cross section lead 44 may be employed. In this case the insert 13 has the portion 35 thereof slotted to form a slot 45 extending from a transverse surface 46 to the lower end 47 of the insert 13. Preferably, in this case also, the slot 45 is formed with chamfers 48 to facilitate causing solder to run into the joints between the edges of the slot 45 and the adjacent surfaces of the bared end 44 of the lead wire.

Certain embodiments of the invention have been shown herein and particularly described and certain methods of operation embraced therein have been explained for the purpose of explaining the principle of operation of the invention and showing its application, but it will be obvious to those skilled in the art that many modifications and variations are possible and it is desired therefore to cover all such modifications and variations as fall within the scope of the invention which is defined in the appended claims.

What is claimed is:

l. A power supply connection assembly comprising in combination:

a power supply connector block having a conductive connector terminal therein, the block and the connector terminal having lower plane surfaces lying substantially in the same plane,

a connector for cooperation with the power supply connector block comprising:

a. first and second blocks of insulating material,

b. a connector insert composed of electrically conducting material,

0. means for securing the connector blocks to each other,

the first block having 1. first and second plane surfaces, and 2. an opening extending from one plane surface to the second, of such dimensions as to make a slip fit with the insert,

the second block having l. a plane surface adapted to fit against the second plane surface of the first block, and

2. a socket extending from said plane surface into the block, of such dimensions as to make a slip fit with the insert,

the insert resting within the space formed by said opening in the first block and the socket in the second block, being of greater length than the distance between said plane surfaces of the first block and having an upper end plane surface, adapted to lie in the plane of the first surface of the first block,

The socket in the second block registering with the opening in the first block, and the combined depth of the opening and the socket being sufficient to receive the insert with adequate tolerance to permit close fit between the insulator blocks with the end surface of the insert in the plane of the first surface of the first block, and

means for drawing the upper end surface of the insert into engagement with the lower surface of the power supply connector terminal.

2. A connector comprising in combination:

a. first and second blocks of insulating material,

b. a connector insert composed of electrically conducting material, and

c. means for securing the blocks to each other,

the first block having 1. first and second plane surfaces, and 2. an opening extending from one plane surface to the second, of such dimensions as to make a slip fit with the insert,

the second block having 1. a plane surface adapted to fit against the second plane surface of the first block,

2. a socket extending from said plane surface into the block, of such dimensions as to make a slip fit with the insert, and

3. a groove extending along the surface of the second block to the insert receiving socket therein, adapted to receive a conductor,

the insert resting within the space formed by said opening in the first block and the socket in the second block, being of greater length than the distance between said plane surfaces of the first block, and having an upper end plane surface adapted to lie in the plane of the first surface of the first block, the insert also having a transverse opening therein substantially in alignment with said groove and spaced from the said plane surface of the second block to receive the end of a conductor adapted to lie in said groove,

the socket in the second block registering with the opening in the first block, and the combined depth of the opening and the socket being sufficient to receive the insert with adequate tolerance to permit close fit between the insulator blocks and the end surface of the insert in the plane of the first surface of the first block.

3. A connector as described in claim 2, in which there is a plurality of inserts, the first block has a plurality of openings to receive inserts and the second block has a plurality of sockets to receive the inserts and the first surface of the first block is adapted to fit against the plane surface of a connector unit having conductor means therein with an electrical connection surface in said plane.

4. A connector described in claim 2, wherein the means for securing the blocks to each other comprises nut means embedded in the second block and screw means extending through the first block adapted to be threaded into the nut means, the first block having counterbored sockets to receive the screw means and the second block having openings registering with said counterbored sockets to admit the screw means.

5. A connector as described in claim 2, in which the groove is axially elongated to allow axial movement of the insert carrying a conductor surrounded by sleeving extending into the groove.

6. A connector as described in claim 2, wherein the length of the insert is less than the combined thickness of the first and second blocks.

7. A connector comprising in combination:

a. first and second blocks of insulating material,

b. a connector insert composed of electrically conducting material, and

c. means for securing the blocks to each other,

the first block having 1. first and second plane surfaces, and

2. an opening extending from one plane surface to the second, of such dimensions as to make a slip fit with the insert,

the second block having 1. a plane surface adapted to fit against the second plane surface of the first block, and

2. a socket extending from said plane surface into the block, of such dimensions as to make a slip fit with the insert,

the insert resting within the space formed by said opening in the first block and the socket in the second block, being of greater length than the distance between said plane surfaces of the first block, and having an upper end plane surface, adapted to lie in the plane of the first surface of the first block,

the socket in the second block registering with the opening in the first block, and the combined depth of the opening and the socket being sufficient to receive the insert with adequate tolerance to permit close fit between the insulator blocks with the end surface of the insert in the plane of the first surface of the first block, the connector insert being formed with a hexagonal portion and one of the blocks of insulating material being formed, in the insert receiving portion thereof, to conform in shape with a loose fit with the hexagonal portion of said insert.

8. A connector as described in claim 7, in which the opening in the first block of insulating material has a hexagonal portron.

9. A connector comprising in combination:

a. first and second blocks of insulating material, b. a connector insert composed of electrically conducting material, and

c. means for securing the blocks to each other, the first block having 1. first and second plane surfaces, and 2. an opening extending from one plane surface to the second, of such dimensions as to make a slip fit with the insert, the second block having 1. a plane surface adapted to fit against the second plane surface of the first block, and 2. a socket extending from said plane surface into the block, of such dimensions as to make a slip fit with the insert, the insert resting within the space formed by said opening in the first block and the socket in the second block, being of greater length than the distance between said plane surfaces of the first block, and having an upper end plane surface adapted to lie in the plane of the first surface of the first block, the socket in the second block registering with the opening in the first block, and the combined depth of the opening and the socket being sufficient to receive the insert with adequate tolerance to permit close fit between the insulating blocks with the end surface of the insert in the plane of the first surface of the first block, the insert being formed with a threaded bore to receive a screw for drawing the insert to the position with the upper end surface in the first plane surface of the first block. 10. A connector comprising in combination:

a. first and second blocks of insulating material, b. a connector insert composed of electrically conducting material, and c. means for securing the blocks to each other,

the first block having l. first and second plane surfaces, and 2. an opening extending from one plane surface tothe second, of such dimensions as to make a slip fit with the insert, the second block having 1. a plane surface adapted to fit against the second plane surface of the first block, and 2. a socket extending from said plane surface into the block, of such dimensions as to make a slip fit with the insert, the insert resting within the space formed by said opening in the first block and the socket in the second block, being of greater length than the distance between said plane surfaces of the first block, and having an upper end plane surface adapted to lie in the plane of the first surface of the first block, the socket in the second block registering with the open ing in the first block, and the combined depth of the opening and the socket being sufficient to receive the insert with adequate tolerance to permit close fit between the insulator blocks with the end surface of the insert in the plane of the first surface of the first block, the connector insert being formed with a collar of greater diameter than the remainder of the insert and spaced from the ends of the insert and the opening in the first block of insulating material being formed with an overhang at the first surface thereof, of less diameter than the remainder of the opening to retain the insert in said opening.

11. A connector as described in claim 10, in which the axial dimensions of the overhang and the spacing of the collar from the end of the insert limit axial travel of the insert.

112. A connector comprising in combination:

a. first and second blocks of insulating material, b. a connector insert composed of electrically conducting material, and

c. means for securing the blocks to each other,

the first block having 1. first and second plane surfaces, and

2. an opening extending from one plane surface to the second, of such dimensions as to make a slip fit with the insert,

the second block having 1. a plane surface adapted to fit against the second plane surface of the first block, and

2. a socket extending from said plane surface into the block, of such dimensions as to make a slip fit with the insert,

the insert resting within the space formed by said opening in the first block and the socket in the second block, being of greater length than the distance between said plane surfaces of the first block, and having an upper end plane surface adapted to lie in the plane of the first surface of the first block,

the socket in the second block registering with the opening in the first block, and the combined depth of the opening and the socket being sufficient to receive the insert with adequate tolerance to permit close fit between the insulator blocks with the end surface of the insert in the plane of the first surface of the first block, one of the blocks being formed with a lateral extension to the insert-receiving socket adapted to receive a conductor.

13. A connector as described in claim 12, in which the insert-receiving socket of the second block has a lateral extension for receiving a conductor.

14. A connector as described in claim 2, in which the insert is formed with a transverse recess therein, substantially in alignment with said lateral extension to the insert-receiving socket.

15. A connector as described in claim 14, in which the transverse recess in the insert extends in an axial direction toward the lower end thereof to receive rectangular cross section conductors.

16. A connector as described in claim 12, in which the lateral extension is axially enlarged to allow axial movement of the insert carrying a conductor.

17. A connector comprising in combination:

a. first and second blocks of insulating material, b. a connector insert composed of electrically conducting material, and c. means for securing the blocks to each other,

the first block having 1. first and second plane surfaces, and 2. an opening extending from one plane surface to the second, of such dimensions as to make a slip fit with the insert, the second block having I. a plane surface adapted to fit against the second plane surface of the first block, and 2. a socket extending from said plane surface into the block, of such dimensions as to make a slip fit with the insert, the insert resting within the space formed by said opening in the first block and the socket in the second block, being of greater length than the distance between said plane surfaces of the first block, and having an upper end plane surface, adapted to lie in the plane of the first surface of the first block, the socket in the second block registering with the opening in the first block, and the combined depth of the opening and the socket being sufficient to receive the insert with adequate tolerance to permit close fit between the insulator blocks with the end surface of the insert in the plane of the first surface of the first block, the connector insert being formed with a polygonal portion and one of the blocks of insulating material being formed, in the insert-receiving portion thereof, to conform in shape with a loose fit with the polygonal portion of said insert. 18. A connector as described in claim 17 including means for drawing the upper end surface of the insert to the first plane surface of the first block. 

1. A power supply connection assembly comprising in combination: a power supply connector block having a conductive connector terminal therein, the block and the connector terminal having lower plane surfaces lying substantially in the same plane, a connector for cooperation with the power supply connector block comprising: a. first and second blocks of insulating material, b. a connector insert composed of electrically conducting material, c. means for securing the connector blocks to each other, the first block having
 1. first and second plane surfaces, and
 2. an opening extending from one plane surface to the second, of such dimensions as to make a slip fit with the insert, the second block having
 1. a plane surface adapted to fit against the second plane surface of the first block, and
 2. a socket extending from said plane surface into the block, of such dimensions as to make a slip fit with the insert, the insert resting within the space formed by said opening in the first block and the socket in the second block, being of greater length than the distance between said plane surfaces of the first block and having an upper end plane surface, adapted to lie in the plane of the first surface of the first block, The socket in the second block registering with the opening in the first block, and the combined depth of the opening and the socket being sufficient to receive the insert with adequate tolerance to permit close fit between the insulator blocks with the end surface of the insert in the plane of the first surface of the fiRst block, and means for drawing the upper end surface of the insert into engagement with the lower surface of the power supply connector terminal.
 2. an opening extending from one plane surface to the second, of such dimensions as to make a slip fit with the insert, the second block having
 2. a socket extending from said plane surface into the block, of such dimensions as to make a slip fit with the insert, the insert resting within the space formed by said opening in the first block and the socket in the second block, being of greater length than the distance between said plane surfaces of the first block and having an upper end plane surface, adapted to lie in the plane of the first surface of the first block, The socket in the second block registering with the opening in the first block, and the combined depth of the opening and the socket being sufficient to receive the insert with adequate tolerance to permit close fit between the insulator blocks with the end surface of the insert in the plane of the first surface of the fiRst block, and means for drawing the upper end surface of the insert into engagement with the lower surface of the power supply connector terminal.
 2. A connector comprising in combination: a. first and second blocks of insulating material, b. a connector insert composed of electrically conducting material, and c. means for securing the blocks to each other, the first block having
 2. an opening extending from one plane surface to the second, of such dimensions as to make a slip fit with the insert, the second block having
 2. a socket extending from said plane surface into the block, of such dimensions as to make a slip fit with the insert, and
 2. an opening extending from one plane surface to the second, of such dimensions as to make a slip fit with the insert, the second block having
 2. a socket extending from said plane surface into the block, of such dimensions as to make a slip fit with the insert, the insert resting within the space formed by said opening in the first block and the socket in the second block, being of greater length than the distance between said plane surfaces of the first block, and having an upper end plane surface, adapted to lie in the plane of the first surface oF the first block, the socket in the second block registering with the opening in the first block, and the combined depth of the opening and the socket being sufficient to receive the insert with adequate tolerance to permit close fit between the insulator blocks with the end surface of the insert in the plane of the first surface of the first block, the connector insert being formed with a hexagonal portion and one of the blocks of insulating material being formed, in the insert receiving portion thereof, to conform in shape with a loose fit with the hexagonal portion of said insert.
 2. an opening extending from one plane surface to the second, of such dimensions as to make a slip fit with the insert, the second block having
 2. a socket extending from said plane surface into the block, of such dimensions as to make a slip fit with the insert, the insert resting within the space formed by said opening in the first block and the socket in the second block, being of greater length than the distance between said plane surfaces of the first block, and having an upper end plane surface adapted to lie in the plane of the first surface of the first block, the socket in the second block registering with the opening in the first block, and the combined depth of the opening and the socket being sufficient to receive the insert with adequate tolerance to permit close fit between the insulator blocks with the end surface of the insert in the plane of the first surface of the first block, the connector insert being formed with a collar of greater diameter than the remainder of the insert and spaced from the ends of the insert and the opening in the first block of insulating material being formed with an overhang at the first surface thereof, of less diameter than the remainder of the opening to retain the insert in said opening.
 2. an opening extending from one plane surface to the second, of such dimensions as to make a slip fit with the insert, the second block having
 2. a socket extending from said plane surface into the block, of such dimensions as to make a slip fit with the insert, the insert resting within the space formed by said opening in the first block and the socket in the second block, being of greater length than the distance between said plane surfaces of the first block, and having an upper end plane surface adapted to lie in the plane of the first surface of the first block, the socket in the second block registering with the opening in the first block, and the combined depth of the opening and the socket being sufficient to receive the insert with adequate tolerance to permit close fit between the insulator blocks with the end surface of the insert in the plane of the first surface of the first block, one of the blocks being formed with a lateral extension to the insert-receiving socket adapted to receive a conductor.
 2. an opening extending from one plane surface to the second, of such dimensions as to make a slip fit with the insert, the second block having
 2. a socket extending from said plane surface into the block, of such dimensions as to make a slip fit with the insert, the insert resting within the space formed by said opening in the first block and the socket in the second block, being of greater length than the distance between said plane surfaces of the first block, and having an upper end plane surface adapted to lie in the plane of the first surface of the first block, the socket in the second block registering with the opening in the first block, and the combined depth of the opening and the socket being sufficient to receive the insert with adequate tolerance to permit close fit between the insulating blocks with the end surface of the insert in the plane of the first surface of the first block, the insert being formed with a threaded bore to receive a screw for drawing the insert to the position with the upper end surface in the first plane surface of the first block.
 2. an opening extending from one plane surface to the second, of such dimensions as to make a slip fit with the insert, the second block having
 2. a socket extending from said plane surface into the block, of such dimensions as to make a slip fit with the insert, the insert resting within the space formed by said opening in the first block and the socket in the second block, being of greater length than the distance between said plane surfaces of the first block, and having an upper end plane surface, adapted to lie in the plane of the first surface of the first block, the socket in the second block registering with the opening in the first block, and the combined depth of the opening and the socket being sufficient to receive the insert with adequate tolerance to permit close fit between the insulator blocks with the end surface of the insert in the plane of the first surface of the first block, the connector insert being formed with a polygonal portion and one of the blocks of insulating material being formed, in the insert-receiving portion thereof, to conform in shape with a loose fit with the polygonal portion of said insert.
 3. a groove extending along the surface of the second block to the insert receiving socket therein, adapted to receive a conductor, the insert resting within the space formed by said opening in the first block and the socket in the second block, being of greater length than the distance between said plane surfaces of the first block, and having an upper end plane surface adapted to lie in the plane of the first surface of the first block, the insert also having a transverse opening therein substantially in alignment with said groove and spaced from the said plane surface of the second block to receive the end of a conductor adapted to lie in said groove, the socket in the second block registering with the opening in the first block, and the combined depth of the opening and the socket being sufficient to receive the insert with adequate tolerance to permit close fit between the insulator blocks and the end surface of the insert in the plane of the first surface of the first block.
 3. A connector as described in claim 2, in which there is a plurality of inserts, the first block has a plurality of openings to receive inserts and the second block has a plurality of sockets to receive the inserts and the first surface of the first block is adapted to fit against the plane surface of a connector unit having conductor means therein with an electrical connection surface in said plane.
 4. A connector described in claim 2, wherein the means for securing the blocks to each other comprises nut means embedded in the second block and screw means extending through the first block adapted to be threaded into the nut means, the first block having counterbored sockets to receive the screw means and the second block having openings registering with said counterbored sockets to admit the screw means.
 5. A connector as described in claim 2, in which the groove is axially elongated to allow axial movement of the insert carrying a conductor surrounded by sleeving extending into the groove.
 6. A connector as described in claim 2, wherein the length of the insert is less than the combined thickness of the first and second blocks.
 7. A connector comprising in combination: a. first and second blocks of insulating material, b. a connector insert composed of electrically conducting material, and c. means for securing the blocks to each other, the first block having
 8. A connector as described in claim 7, in which the opening in the first block of insulating material has a hexagonal portion.
 9. A connector comprising in combination: a. first and second blocks of insulating material, b. a connector insert composed of electrically conducting material, and c. means for securing the blocks to each other, the first block having
 10. A connector comprising in combination: a. first and second blocks of insulating material, b. a connector insert composed of electrically conducting material, and c. means for securing the blocks to each other, the first block having
 11. A connector as described in claim 10, in which the axial dimensions of the overhang and the spacing of the collar from the end of the insert limit axial travel of the insert.
 12. A connector comprising in combination: a. first and second blocks of insulating material, b. a connector insert composed of electrically conducting material, and c. means for securing the blocks to each other, the first block having
 13. A connector as described in claim 12, in which the insert-receiving socket of the second block has a lateral extension for receiving a conductor.
 14. A connector as described in claim 2, in which the insert is formed with a transverse recess therein, substantially in alignment with said lateral extension to the insert-receiving socket.
 15. A connector as described in claim 14, in which the transverse recess in the insert extends in an axial direction toward the lower end thereof to receive rectangular cross section conductors.
 16. A connector as described in claim 12, in which the lateral extension is axially enlarged to allow axial movement of the insert carrying a conductor.
 17. A connector comprising in combination: a. first and second blocks of insulating material, b. a connector insert composed of electrically conducting material, and c. means for securing the blocks to each other, the first block having
 18. A connector as described in claim 17 including means for drawing the upper end surface of the insert to the first plane surface of the first block. 